Just to provide some context and actual numbers @jeverstones, a CGC 7 Blastoise Illustrator Error sold for $600 on 6/7/23 and a CGC 3.5 sold for $204 on 6/4/23. There are currently a few copies for sale on eBay: CGC 6 for $1,133, CGC 4.5 for $848, and a raw copy for $750.
Realistically, your card is worth somewhere around $2,000-$3,000 to the right person. I collect these types of errors and I would pay $2,000 for a PSA 9 and $1,000 for a PSA 8.