I'd say that you would want the lab to be lookin' for excess combustion by-products... my guess (since you say the coolant is fine, and there's no "chocolate shake" in the oil, that IF you do have a head gasket leak, it's between the CC and the oil passages, not involving the coolant, if that's possible.)

How many miles on that gasket ?

I don't know of a lab near you, but you might wanna check out Blackstone labs. I would call them and ask if they could drop a sample kit in the mail for you, instead of requesting the kit online. You can take a sample in any container if you are looking to get that oil changed ASAP. Just use a clean tupperware container, you only need a few ounces, then when you get the kit, pour it in and send off.
Which reminds me, I need to mail out a sample myself! Been sittin' on the shelf for two weeks now.