If it's embedded in plastic, I'd say it would be worth $5-10 as a souvenir. If it can be removed, probably more like $20-50 if you can find the right token collector. However, you never know what will turn a collector on. At a general-public auction like eBay, Sands items sometimes go wild. Sands common $1 chips (blue or orange) typically sell for $8-12!

I just noticed your note title said "SPT"; does that mean this is a big .999 silver item? If so, I'll have to defer to Marv who may know what these monsters go for. My first thought was that this was a high-roller slot token.

DonL