Your gut feeling fits ok with what little price data I've got. Perhaps a little optimistic. Did you find my pricing work? Sample sizes are still small, but I consider it a bit better than squat:

http://black.net.nz/old-k/old-k-prices.html#15

Because of small sample sizes I include Turkish made K Constantinople cymbals in with Old Stamps in my analysis. But they don't yet stand out as anything different in terms of pricing. Many K Constantinople cymbals seem to be less favored because they are Band cymbals and heavier in weight, as you see from yours. They seem to fit into the "older and rare but maybe more suitable for collecting than playing" category.

Thank you.

I kept your pricing from an Istanbul ride I'd asked about, so yes. I didn't know how it fit exactly into your schema but I got the gist. Would you like what they go for? I can PM you,

Chris

Yes that would be great. With data so scarce every little bit helps.

Given that weight they could be orchestral cymbals.

As for pricing, a 15-3/4" heavy 1st stamp cons just sold on eBay for $338.

Thanks for that. An item number will allow me to locate it easily. The software here means you can't put in a full ebay link as it gets edited out. I've never found out whether that's a bug or a feature. I've had a look but didn't find it. I did find an earlier one

item # 121893175311

16.5" $175 on the 15th of Feb 2016 (which again underscores the degree of variability in prices)

Link: http://goo.gl/6E8GXZ

(using a URL outsmarts the ebay link removal software)

item #381550194854