The Shulchan Aruch (y.d. 102:3) cites the Rashba that if a spoon that became treif gets mixed up with kosher spoons, we can allow bitul. It is not considered a davar sheyesh lo matirin, since there is an expense that one incurs by kashering the spoons (in those days they probably had to either schlep the water or pay for it to be carried to their homes). The Shach (8) quotes the maharil that this is only true if the expense is significant, but a minor expense is still considered "yesh lo matirin" and therefore it would not be batul. The proof is from our gemara that considers ma'aser shein outside of yerushalayim to be yesh lo matirin since it can be brought up to yerushalayim. Under normal circumstances there is an expense to go up to yerushalayim, yet we consider that expense insignificant and consider the aliya to yerushalyim to be yesh lo matirin.
Based on Tosafos in our sugya, there wouldn't be any proof from our gemara. Tosafos points out that the gemara discusses the idea of aliya to yerushalayim as being "yesh lo matirin" only on the ma'aser sheini that was brought in and then taken out, but doesn't bring this up in the case of less than a shava peruta of ma'aser sheini - why? Tosafos explains that the aliya to yerushalayim is a major schlep and therefore is not considered yesh lo matirin, under normal circumstances. But, in the case where the ma'aser sheini was brought into yerushalayim and then taken out, the implication is that he is standing just outside of the city. Therefore, the gemara considers the aliya to yerushalayim to be a "yesh lo matirin", because there is no expense and no real inconvenience. However, in the case of the spoon that gets mixed up, perhaps even a small expense would render it "ein lo matirin" and we can allow bitul.
The Shach rules that in the case of the spoon, you are obligated to wait 24hrs. His rationale is that although the issur d'rabonon is "ein lo matirin" (due to the expense of hag'ola), the issur d'oraysa of using the spoon as a ben yomo is "yesh lo matirin". The shach seems to assume that by davar sheyesh lo matirin, if one can remove the issur d'oraysa, even though he cannot remove the issur d'rabonon, he must remove the issur d'oraysa and only then do we allow bitul. I have a question on the shach from our gemara. The gemara says that once the ma'aser sheini has been brought into yerushalayim and taken out, on a d'oraysa level one can still redeem it, but on a d'rabonon level it cannot be redeemed (mechitzos are koltos m'drabonon). The gemara says that one can eat the ma'aser sheini through bitul and does not need to redeem it to remove the issur d'oraysa. We see that if the item is not going to be completely permitted, even if one can remove the issur d'oraysa, it is still called ein lo matirin since the issur d'rabonon would remain. Therefore, in the case of the spoon we should also allow him to use the spoon within 24hrs and not have to wait to remove the issur d'oraysa?
One of the very astute attendees of my daf yomi (Guy Wilnai) offered a very logical distinction. When the d'oraysa can be removed we consider it a yesh lo matirin to remove the issur d'oraysa, and only then to we allow bitul to work, as the shach explains. But, in our gemara the issur d'rabonon is not to redeem outside of yerushalayim. The reason we cannot redeem it to remove the issur d'oraysa is because the redeeming itself would be a violation of the issur d'rabonon not to redeem it. Therefore, we consider it ein lo matirin and allow bitul. [There is a big chiddush in this approach. Presumably, chazal never said that there is an issur to redeem after it has been brought into yerushalayim and then taken out. Rather, they said that mechitzos are koltos so that redeeming doesn't work to remove the status of ma'aser sheini - but there isn't any issur in doing the act of redeeming. The above approach assumes that this is NOT correct - we consider there to be an issur it even attmepting to redeem it after it has been brought in and then taken out].