Mail order parts are always a crapshoot. There are dealers that I absolutely refuse to buy "Part A" from, because I've gotten burned in the past, but "Part B' has always been a good piece at a fair price.
I agree wholeheartedly that shipping costs play a major part in selecting sources. Some dealers charge actual shipping costs, plus a small fee for processing the order. Others base the cost on the value of the order, and can really stick you.
I'm sometimes amazed, that the shipping on a part from California, to Michigan, on an item that costs $750.00, is much less than what I get charged for an item costing $200.00, when shipped from another Midwest location.
I guess the best thing to do is ask questions at places such as this forum, and for any specific recommendations, set up a back channel email. Then we can give you our sob stories, or tales of glowing praise.
One thing though, if you do receive a part from ANY supplier, that is sub-standard for any reason, let them know about it! If they don't know there is a problem, they can't fix it. I've had several issues resolved to my satisfaction over the years by just letting them know!
Didn't mean to rant!
Bugeye58