Hawk 250 // 520 Chain rear sprocket

[dzl862]

I’ve read the main info page for the Hawk 250 on this forum and it mentions that you can get JTR279 sprockets in up to 42 teeth for a 520 chain. I can’t seem to find any of that specification. I’ve found a few that have six holes for the studs, but those won’t fit on the hawk, since it has four in a square pattern, and these sprockets wouldn’t fit the snap ring that holds the rear sprocket on either. I have found one that would fit on the hawk, but only has 30 teeth. I really would like to have 38 at the very least, preferably 42. I’ve found a couple weird, one-off 42 tooth sprockets that may fit, but they are either out of stock, being sold overseas, or on a very shady website. Does anyone have a link that I could use to buy a JTR279 38/40/42 tooth rear sprocket? The attached links are: the 30 tooth, which has the right position for the sprocket stud holes, and the 40 tooth, without the right sprocket stud holes.
JT Sprockets JTR279.30 30T Steel Rear Sprocket , black , 30 Tooth https://www.amazon.com/dp/B0034B0R3M...ZB56QKZ6?psc=1
JT Sprockets JTR279.40 40T Steel Rear Sprocket https://www.amazon.com/dp/B006SRYGFO...YA8ZBKV3BWBP1B