Elephant ivory grips aren't all that difficult to find, there are a number of reputable dealers out there and they're readily available on gunbroker as well, and prices have been in the $300+ range for a long while. Currently the bigger issue with buying ivory grips are the new laws regulating importation and shipping across state lines. This has resulted in an increase in popularity of mammoth ivory grips, which aren't subject to the same regulations, however, there is, of course, a limited supply of raw material out there. These supply issues and the impact on the cost of ivory products have resulted in an increasingly wide variety of natural materials from different animals finding their way to the handgun grip market - water buffalo bone and horn, camel bone, bison bone, ram horn, giraffe bone, moose antler, caribou antler - and I'm sure there are others I haven't seen yet. Prices are directly related to the scarcity of the raw material as well as the country where the grips are being produced.
I have a couple of sets of very nice elephant ivory grips I bought last spring before the new laws took effect. I also have mammoth ivory, camel bone, buffalo bone, stag, and Tru-Ivory bonded ivory. They all look and feel good, though all of the buffalo bone and stag grips I've had are thicker than standard.
Something you might consider is holly wood, it's a white wood and when cut into grips it looks and feels very much like ivory, also very reasonably priced. A couple of coats of Tru-oil and it gets a look similar to aged ivory. I can't afford to put ivory on all of the guns I'd like to and holly is a cost effective way to get a similar look and feel.
