Try one of these. It worked great for me when I had a TiVo in a cabinet.
Same as the unit Arcady mentioned as being sold by Weaknees. Your price is lower, if you search you might find it for a little less. Buy.com had it for $34 shipped earlier this year.I know this is an old thread, but after doing a lot of research, the Next Generation Remote Control Extender from Amazon seems to be the best solution at the best price:
http://www.amazon.com/Next-Generati...1?ie=UTF8&s=electronics&qid=1206615407&sr=1-1
Under $40 with free shipping. Lots of comments from TiVo owners saying how great this thing works.