Stopped up Snake

I purchased a snake I was told was a female Mexical Milk at the Atlanta show.  I took her home, waited about ten days for her to poop (she didn't) and put her into burmation.  About two weeks before i was to heat he back up, my son noticed that she had a swelling about two inches up from her vent.  I when I raised the tempertature I hoped she would pass whatever it was, but no dice.  I took the animal to the vet and she was rehydriated and given an enima (twice).  It has been two weeks now and the lump is still there.  My vet wants me to bring her in for x-rays and possible surgery.  

Now here is where everyone will probably jump all over me.  The snake cost $35.00, the vet bill was $57.  We all know the snake is not worth much more than $100 as I do not know if she is a proven breeder or not.  If I have to pay a vet for x-rays and surgery, I will never be able to recover the investment in this snake.  I care for all my animals, but in business, you have to know when to cut your losses.

I have not fed this snake and she is lossing weight.  I hate to feed her with the lump there.

What would YOU do?

Have you tried soaking?  I have a corn snake that has been paralized in the rear 1/3 of his body, sense I recieved him a year ago. So he gets poop built up and when I soak him it usually passes on it's own. He is still growing and seems fine. I just don't have the heat to put him down. As for putting any animal down. If it is bussiness. My feeling is not to put more into the animal then you will get back. So if it was me I'd do everything in my power to fix the snake on my own. If I wasn't able to do it. Then I would freeze the snake. This would be a last choice. You have to think of cost and the animal. I have had snakes that won't eat and after about 6+months of force feeding. One day I just tell myself they will eat on thier own or die. 99% of the time they die. I'm not sure if this helps. This is just my opinon but you have to do what you think is best. Thank you for listening to my rant. Frank