Consider allowing an option to combine/fuse equipment. When fusing, allow the user to select which enchantments to keep/etc. This would do the following things:
- It would let people combine gear to get the best enchantments eventually
- It would still cost money for people, so economy sink is maintained.
- It would also make getting gear exciting, since you would always need more gear for fusion. This would keep exploration useful, even into older areas.