Source for screws (nylon and steel) and o-rings in the US

[rconn2]

Am looking for screws and o-rings in the US... here's what I'm finding:

nylon 10-32 and various sizes:
http://www.smallparts.com/products/descriptions/mn-f.cfm

They have lots of o-rings too... silicone and ptfe... not sure which would be best or what size to get offhand though. Prices look very reasonable, just a few dollars, so this looks like a potentially good source. I'd be looking for stuff for epson r220 carts... so not sure if I'd go with #6 size or larger (I'm new at all this)... or if it matters. And not sure how to match an o-ring inner diameter to the #size... will do some research.

Anyone have any comments?

 

[rconn2]

Here's their link for silicone o-rings: http://www.smallparts.com/products/descriptions/ORBK, ORB, MORB.cfm

And for ptfe (teflon) o-rings: http://www.smallparts.com/products/descriptions/ort.cfm

The silicone ones are cheap... like $5 or so for a hundred of the smaller diameter ones. The teflon's are more expensive, but still not much. I haven't ordered anything here, but am looking for a better, more consistent, method for plugging/unplugging refill holes than stupid blue plugs that you chop the end off and leak when they don't fit right.