I have a black capacitor with the code 503 on it(see attached image). The best I can tell its a 16v .05uf capacitor(mylar?) Not sure where it came from just found it in a bin of loose parts and I need to find a few more for a project. The only place I can find them I have to purchase a ton >:( >:( of them or they have some minimum order amount and I have purchase crap to just hit the limit. Anyone know a good place I can purchase capacitors at without having to purchase a whole ton of them. I checked the local frys and they were either sold out or do not have them
Its a ceramic disc capacitor by the look of it.
If you want advice on purchasing you need to at least tell us which country you are in...
First check that it is a capacitor. The black encapsulation is very unusual for a ceramic capacitor (which is the only sort of capacitor it would be).
Looks like a 50k NTC.
Try to measure the resistance.
Leo..
Thought as much. 
The best I can tell its a 16v .05uf
The value is correct.
I don't know how you obtained the voltage rating.
It looks like Mylar
I think you have missed the link in post#3
Leo..
There is a distinct similarity ... ;D
Wawa:
Looks like a 50k NTC.Try to measure the resistance.
Leo..
Couple days late but you are awesome this Is exactly what I am looking for. I live in the Texas if you know any good US places to buy.
I'd just mail order them from Tayda. Great prices, usually relatively decent shipping. Exactly where I got mine. Note the Tayda part numbers if you want to buy there.
http://www.taydaelectronics.com/catalogsearch/result/?q=thermistor
Well, there’s the trick.
As so often happens here, the OP is not too flash with the English language.
In the first post, he said he was looking for capacitors.
AgentNoise:
Anyone know a good place I can purchase capacitors at without having to purchase a whole ton of them.
Now we have determined that the object in question is not a capacitor, but a NTC thermistor.
He now says ambiguously
AgentNoise:
this Is exactly what I am looking for.
So we are now uncertain what he is actually looking for - the information about the component not being a capacitor, or a supply of capacitors, or he really did want NTC thermistors! 
Another satisfied customer (who didn't know what they wanted ..) finds exactly what they were looking for.
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We Texicans don't speak English, we speaks Amuricin! We ran the English out a couple a hundred years ago. Actually, the Yankees ran 'em out, we are just stuck with them Yankees now....
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Op, AgentNoise, have y'all tried E-bay, or Amazon? Get capacitors. if you don't know the difference, you ain't ready for thermistors yet.
Tayda has a very good selection of capacitors too. I'd get a few of everything. Come to think of it, I already have... 
123Splat:
- We Texicans don't speak English, we speaks Amuricin!
Must be hard for you with English not being your native tongue.
Sometimes, not as hard as it appears to be for some Britts, for whom English is their native tongue (or maybe it's just because we tend to bastardize the lingo and spell differently).
We Texicans don't say "I live in the Texas " !
So he may live in Texas now, but he is not a Texican.
If he will tell us what he is looking for, we can probably help him find it.
Wawa:
Looks like a 50k NTC.
Probably useless by now, but I can confirm this, as I have the same part.
Yes, well, the OP seems to have had his fun and left.