Vet Bill for Sidney

I am on SSI/SSDI and can't afford to pay $500 for a vet bill.  My cat Sidney is 11 years old and needs some tests (xrays and blood work) to determine why he is losing weight.  I just lost my other cat Erik to kidney disease in February so I am really worried that I will lose Sidney if I don't get him help right away.  I have a disability and my cats are my companion animals so losing both of them would be very painful for me.  I have had Sidney since he was a kitten and he is the love of my life.  I will be so grateful to anyone who makes a contribution.