Steven,
You are very close on the age of your steins, around the 1990’s. Look in the Reading Room for Stein Marks to find the maker BMF C. Koch in Nürnberg. I would think your glass and transfer steins would be about $10-20. They could be pretty good starters for a collection. Look for more glass or spread to the many other types of materials.

Maybe not real old – but very attractive and good addition to a collection.