The 20 gauge configuration will be worth more than a 12 gauge, but the 200 series was their "entry level" O/U gun. It appears to be in good condition, from your photos, which I assume were taken with a quickie digital camera. If the condition is indeed good overall, no bore problems, I would guess perhaps $1,500 or in that general range, more if the condition proves better, less if problems show up on a close examaination. It likely has tight chokes, which limits it's use as a unpland gun. If there is a large gun shop nearby, you might get their opinion, and have the chokes actually measured. A Model 201 in 20 gauge would likely bring $500 more, maybe even a bit more than that. To my eye, this looks like a Model 200 gun. There should be a date code in the proof marks to show when it was actually proofed, something like 938 would mean Sept. 1938.
