Like you said mate, "don't want to rush in and get the wrong dog" .... So you know what type/cross that you are looking for, just keep your eye's peeled for suitable litter's.
Then go and have a look .... "But" as you have waited for the right pup to come along don't take a pup for the sake of it because you are there at the time. If the litter isn't that pleasing on the eye for some reason or another walk away . . .
Best of luck mate