Question about Oil Leak and a Breather?

I have 2 oil leaks it seems, my front main and rear main seals. I want to get these fixed but am waiting for the weather to be better. My car is my daily driver and I was just wondering if I put a breather on would it make my seals leak less? Would this cause more problems? Also is there any place that just sells a vented oil cap?

Thanks

Thanks guys for the info...Also I just have one other question that is going on with my oil pressure. I still have the stock gauge and everyone says it is a dummy but this is what I have been noticing with mine. Normally mine sits straight up and down or maybe a little bit more to the right. Recently my car has been sitting down to the left a little bit and the needle doesnt go up to that fast anymore. Also it will still have the days or random start ups where it does still sit straight up and down. Is there any cause for this? Could this actually be because my seals are so bad that they are loosing pressure out of them?

Thanks,

Dan