Here's a much better set.  Eight chips for less than $10.   Still may not be the right chips, but if the part numbers don't match, don't assume they won't work.  Post the part number you do need.  Then we can maybe find a datasheet and see if they're the same part from different manufacturers.

http://www.ebay.com/itm/8-TC524258BZ-80-DUAL-PORT-VIDEO-RAM-256Kx4-512x4-150-30ns-5V-ZIP-28-DRAM-VRAM/271632014082?_trksid=p2060778.c100276.m3476&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D20140725133649%26meid%3D9654b2767c8041d983a7e9413fedc0d9%26pid%3D100276%26prg%3D20140725133649%26rk%3D2%26rkt%3D4%26sd%3D121291981557