Like the 2101 the 621 is truly legendary. The very first "modern" saw on the market....when it first came out it was called the 62.....and was developed from the old 601.......at the time no one else had figured out AV or the whole piston ported thing.......most all saws were still reed valve motors......a Cadillac of saws. These are not a large displacement saw motor at 56cc or wicked fast but are very strong and will pull a 20" bar with full chisel all day long in hardwood and not break a sweat. They last forever.....they were spendy compared to US saws.....if I remember right around $350.00-$400.00 in the early/mid 70's. I could go on and on......I have 3...all very good running used examples.....and nearly enough NOS parts to build another one.....still missing a few bits.
To the poster of this fine unit......That one sure is nice...if you still have the box DO NOT destroy it.....and don't start it either....to the right collector, with deep pockets...having the original box will nearly double it's worth. As to what it's worth???? I would have no idea but $5-$600.00 wouldn't surprise me. Done right it can be a sellers market. There was a beautiful one on ebay a few yrs back....the guy built it from all NOS parts......did a great job and a super presentation...very nice photography....class act right down the line.....damn thing only brought $250.00 at auction .........I felt bad for the guy......thought it worth much more.....
Nice history lesson on the 621, Robin! I too feel sorry for the guy that built one from NOS parts...but in truth, that saw had no provenance to a collector. To me, I see no difference if done right and would pay accordingly.
If the OP's saw was presented properly with lots of pictures and hell yeah, a box and a healthy reserve on ebay...he should do well.
Kevin