Yeah, TK - many of the newer crop of satellite radios incorporate built-in tuneable FM transmitters. enabling any FM radio to reproduce their signal. Depending on listening room layout, you may or may not need an inexpensive antenna extension cable (the antenna - which is pretty small - needs a good view of the Southern sky). There is a wealth of content on Satellite, and since overall absolute audio quality is not a major factor, I think satellite radio could be your best bet.
I recommend the
Delphi Roady XT; it is the smallest, lightest XM receiver available, the basic unit can be had for under US $50, the accessory
Home Kit is also available for under US $50 (but you can get away without it - mebbe) its FM output can be set to any FM frequency so nearby station interference is no problem, it has a very bright, crisp, legible display, it has lotsa user convenience features (really worth reading the short, clear manual that comes with it), and its audio quality is among the best of class for satellite radio. I have 2 of 'em, and I'm very satisfied.
Now, about that home kit ... what it amounts to is a tabletop docking cradle, an antenna, a remote control (pretty handy), and a wall-plug power supply. In your case, its prolly worth the extra bucks. Personally, I don't have one; 12-Volt power is no problem here (I have all sortsa converters and transformers, and the unit draws very little power - a cheap 110/12V cigar-lighter-socket converter would work fine), and I've just checked to make sure and I found the unit works fine in its FM mode when set on a windowsill several feet from my A/V rig, with its antenna run out through a window (the antenna lead is about 18' long, and the cable is very thin - the window can be closed over it without problem). The only thing I give up is remote control, and I even found a way around that, using a programmable remote control (though it is a pretty pricey, sophisticated remote - I don't recommend you go that way, I just happened already to have it).
There also are a couple dedicated, self-contained tabletop/boombox mounts available - dunno why you'd wanna go that way though, since you've already got a decent tabletop radio the basic unit can transmit to, and it doesn't seem taking it to the beach is on your "Gotta Do" list. Anyhow, for under a hundred bucks, plus the subscription cost ($12.95/mo, I think there's a break if you take an annual subscription), you should get everything you need to accomplish what you're after - far less cost, far more variety than HD Radio, even given the subscription cost, at least over a period of a few years, given the cost of the current crop of HDR-capable tabletop radios.