Front Caliper Banging On Mount

[Gradywhite]

I have a 2000 Escalade. I've been having alot of rattling in the front drivers side for at least 6 mos. Finally took it to a brake center and they showed me the problem. The caliper doesn't fit tight within the mount. I can probably slip a penny or dime between the top of the caliper and the corresponding surface of the mount. The result is the caliper rattles back and forth as I drive.This has resulted in the two surfaces wearing down or peening over thereby increasing the gap. Mechanic stated that on some years the Tahoe had shims to take up this space, but it appeared this year was not one of them. Their solution was to just replace the caliper, probably fm NAPA. I replaced these calipers in '05 and have approx 20K on them. My guess is the caliper when new was a hair too short in length, thereby allowing the rattling to begin. I declined their suggestion.
I think the smart thing to do is replace the caliper AND mounting bracket. Maybe I should stay away from NAPA calipers also.
Any thoughts?