Paid $282.50 OTD for my E-series ADL - in similar condition - a couple of years ago. And mine too bears only the A stamp thus:
Here is an early 336A-DL listed today on Gun Broker. Most likely because it is not roll-stamped "A-DL" on the barrel, it is identified as an "A" model; but it does have the A-DL factory checkered stocks and the A-DL large swivel studs. The owner has started the auction at $475, and I seriously doubt it brings much more than that amount, as this is about tops for an early A-DL in this condition.