Anybody offering a service to do this for Pokemon Gold?

i do. but i dont solder it.  i do tape and super glue to make sure it stays.  i do soldering with full size game though

^^And your superglue technique will make future battery swaps impossible...

i dont glue the battery.  i wrap some electric tape very tightly around the battrey.  before i secure the tape, i put super glue lightly on the top first layer of tape and and secure it down.  ive been doing that for years and it works.  all it takes is a razer blade to remove the tape

Not to be an entitled internet poster, but I am curious if it has been determined whether or not one of the battery holders listed on ebay will fit in the case for the memory pak. Honestly, after buying it I was a little mad at myself for not just getting a third party unit, but oh well.

depending on the battery size, there might not be a good holder for gameboy games.  there is one that a member found and had a group buy for some though.  i dont recall what size it fits, however.