In between Mike P.'s suggestions lay the Hart and Wichita (sp) Rests. These are cast iron like the Sinclair, a little extra weight doesn't hurt, and they will accept any of the popular upgrades for the Bald Eagle and Sinclair rests. A little side note, Sinclair hasn't always made their own rests. They would use the Hart pedistal and attach their own goodies to it.
Monies and points of reference
Caldwell = ~$80.00 - Midway, Midsouth, a few others
Wichita = ~$130.00 - Lock Stock & Barrel, Midway [on the internet, not in their catalog]
Hart = ~$170.00 - About the only place I've found them is on the Hart Website
Sinclair - ~$175.00-$400.00 Sinclair Internetional Website/Catalog depending on options
Bald Eagle - ~$175.00-$400.00 Bald Eagle Website depending on options
These prices are approximate and it should be noted that many many options are available and will quickly drive the prices up. Also these prices do not include the bag, Good baggs run about $30.00.