Based on the comments in the OP, RJ is not interested in sprung trucks. So there are exactly four options for "solid" T-section Bettendorfs in HO scale.
Only the Kadee is currently offered as a stand-alone part. They are nicely done, although I am not a big fan of the "self-centering" feature.
I have freed up a couple of MTH and Red Caboose sets by swapping as was mentioned earlier. But it's a limited resource for most of us. The Walthers 1009s are meh, but can be had fairly cheap on eBay.
I can't be optimistic about any "new" offerings. Unofficially at least, Brian Leppert is on record as being retired from doing any new TMW tooling. It sounds like Owl Mountain is set for quite a while with their existing stash of RC trucks. I plan on working with the status quo, but of course would welcome any good new when it comes to pre-1920 truck designs.
Swall Meadows, CA