Sunline T1950 2002 TT

Hi, I was hoping I could get some help. I need a black water tank for a 2002 sunline T1950. I measured the tank and it’s a 60x21x8 if I measured correctly. So far I’ve had no luck. Any suggestions for a supplier? TIA

Edit: I’ve checked the suppliers you listed and didn’t find one the right size. Any possible suggestions would be appreciated