My Harmony controls my RCA DVR40 just fine, so did my old Marantz RC2000. Any remote that works with Tivo should work with the RCA, and I've never met a learning remote that didn't, though the sensor on the RCA is a bit finicky about strength and direction.
Harmonys can be had a for under a hundred on eBay and Marantzs can be had there dirt cheap.
Harmonys can be had a for under a hundred on eBay and Marantzs can be had there dirt cheap.