Tonearm for Luxman PD 441

I have a late 70's Luxman PD 441 turntable with a Grado The Reference high output cartridge that I really like.  I'm thinking that my weak link is the old Denon DA 307 tonearm with that goofy rubber for damping.  Any suggestions on an easy switch for under $1,000, even used?  Thanks all.
I use Luxman TA-1, Victor UA 7045 and Lustre 801 on my Luxman PD-444. They are all under $1000 and works great for mid/high compliance cartridges (lustre works great with low compliance as well), but you need different luxman's arm bases for different arms. 
Thanks for the advice.  I've never attempted a tonearm mounting before.  Just cartridge changes.  Am I in for a lengthy and confusing process?
That's why i bought Dr. Feickert protractor. If your arm does not come with original template you need to measure spinde to pivot distance correctly. Your Denon tonearm fits Luxman tonearm base (model TP-SG) with single small mounting hole. Tonearm with larger shaft doesn't fit into this tonearm base hole. Luxman provided different tonearm bases for different arms, those bases goes for $200 each and quite rare and hard to find. TP-MT base made for tonearms fixed by 3 screws (fidelity research, saec, micro...). And for large armbase shaft (like Technics EPA-100, Victor 7045, Lustre 801) luxman made tonearm base with large hole, model TP-LH. There is also special luxman tonearm base for SME only, model TP-LS. So when you are looking for new tonearm make sure your tonearm base is compatible. 
Thanks for the heads up.  I wonder how I find options that will fit similarly to the existing Denon arm?  I'd rather not get into chasing down rare and expensive tonearm bases.  
SME III with top MMs (high compliant) like SHURE ULTRA 500, Audio-Technica AT-180ML/OCC and Grace F-14 fits nicely the LUXMAN PD444 in sound quality IME. Indeed you would need a special arm bracket for SME arms. Good luck.
Fidelity Research FR-64 had the same 230mm mounting distance , is a drop in replacement of the DA307.
I have a PD-441 with a Fidelity Research FR64s, the optional vertical height adjuster, and a Yamaha MC-1s moving coil cartridge. It is my second-tier table, but I am very pleased with (and actually surprised at) how good these pieces sound together, plus they look absolutely fantastic.
Seems like the Fidelity Research FR 54 is a lot less expensive to buy than FR 64.  Is there much of a difference?  They both seem to be same dimensions, so should work with my PD 441
Could you not just get a local woodworker/vinyl enthusiast to make a tonearm board for you? That's what I do. Usually around 100 to 200 bucks
regarding a tonearm board, I'm not sure how I would attach it to the table.  The spot where the tonearm would attach normally is on a sliding track, so there is seemingly quite a bit of adjustment available to get closer or farther away from the spindle.
After removal the locking armboard you will see that the sliding assembly separates into two pieces: a locking base common to all Luxman 441/445 armboards, and a screw-attached top plate with holes of varying diameter to receive various tonearms. The top plate can be replaced with a custom plate of varying thickness, with a hole of variable diameter to receive any tonearm pillar.