RD 112 fifty: What is it worth?

I have a Music Man RD 112 fifty (serial no. EN 10544) with a 12" EV- speaker in it and original footswitch.
The amp is in good condition, grill-cloth still in good shape, even the numbers (not all) on the knobs have lost some paint.
Maybe needs 2 new 6L6's, but preamp tube is still good, was replaced some time ago. I have no papers, no cover. I bought it used.
Technically also no problems.
What do you think is it worth it?

The 112RD-50 is normally a very desirable amplifier (mainly due to its size... all the right stuff in a small package). I have seen them sell for $600 in mint condition with all the accessories and paperwork.
Average price is probably around $350 to $450 in average working condition (on eBay anyway).
Steve