Antique cymbals are crotales, you'll need the bottom range though, is it a bottom A?
I dont know if you can buy individuals or not but there will be people who may lend them out, I can prob get hold of one, I'm sure Aidan geary has one, and if you ask Ray Payne nicely he might bring one anyway to the areas.
Going on my recolections of the Edward Gregson's "Of Men and Mountains" he wrote for "antique cymbals" in that. Basicaly if you go to a music shop, preferably a percussion specialist, and as for some finger cymbals you should be somewhere near the mark.
Make sure that you get cast finger cymbals, something like Zildjian or LP make, and not some toy sheet metal cast offs.