older phones try pricegrabber.com
or ebay.com.

900 mhz callerid + answering machine uniden_EXAI398
900 mhz callerid + speaker phone uniden_EXI8966
at&t corded models 2-0315A , 2-9432B
Bell phones model 52905 corded Northwestern Bell 39606-M2T 900 Mhz wireless

panasonic
panasonic phone wireless 900mhz model KX-TC1484B
panasonic phone /fax officemax model kx-fHD331 $89 , kx-fhd351 has answermachne fax/phone $119
where i got it things. bestbuy, frys, target, office depot/max,circuit city,sears