This release is probably, by far, one of my least favorite collectibles in retro gaming.
The Sega Master System version of Sonic was the last and final title in US, roughly in October of 1991. This game, along with several others (listed below) were originally released in PAL countries and instead of making an NTSC version, they just slapped some US UPC stickers on the cases and imported them. The reasoning was presumably that the Master System was basically dead in the States by that time. With Sega of America busy pushing the Genesis, these releases would not have been a priority.
Everything about this game and packaging is the same as a European release with with the exception of the UPC sticker placed on the outside of the case.
I believe the other games were Strider, Golden Axe Warrior and Spiderman. Prices for those three are really all over the place depending on how it’s listed and how sick someone is of looking for a copy. You really shouldn’t pay more than $20 – $50 for either of these with patience, although I have seen a Golden Axe sell for $90.
As for Soinc, you are looking at $500 -$1000 in general. This has sold for $900 and $600 in the past, so I’m not sure what the going rate for it right now is.