If what you have happens to be Belden 1189A, then you're probably good to go.
Thanks for your reply. No such luck on the cable...what is installed is labeled:
Coleman Cable RG6/U 18 AWG Type CL2 75c (UL) E100316-I OR CATV 1000MHz Sweep Tested
Seems like I'd be best off with new cable to the receivers, and can use in-wall for backfeed with no issues.