I think any "guilt" that you may feel is of nothing compared with either:
A) The pleasure you will get in three stages, namely:
1) The thrill of actually buying them
2) The thrill again of going to the wardrobe/cupboard/ bedroom floor to have just one more look at them.
3) Wearing them
Then of course you have to factor in:
How you might feel if you decide to buy them, but horror of horrors they aren't there any more!
You do go to look again, decide to buy them but discover they no longer have you size (a word of caution here, DO NOT be tempted into buying a size too small in the mistaken belief that they will stretch enough to be comfortable)
Oh Katek just buy them! I had a similar quandary years ago with a pair of high heeled strappy sandal type things, in emerald green snake skin with gold piping and gold leather lining. I think I wore them all of three times, but boy did I get some pleasure in getting them out of the wardrobe and just looking at them!