alternative to Comp springs?

Hello, can anybody suggest some better springs, as an alternative to the Comp 995-16 (dual) I have bought? These were the recommended springs for the CC XE275HL-XE cam that I have installed in a 68 340 X head engine. Cam is a high lift hydraulic, 0.525/0.525. The springs are, on paper, ideal for this cam as they have a low coil bind number and fairly good open pressure of 336 pounds. Only 115 pound seat pressure though. Rate is 402 pounds.

The reasons I am considering other brand springs is because I measured all these springs carefully on a new Rimac valve spring tester and 70% of them were off the mark. Most were under, some by a lot, and a couple way over in the open pressure. Seat pressure was mostly all pretty close. Also, I believe in the motto: You Get What you Pay For, and these are pretty cheap springs, under US $100 at Summit. Even the labeling was shoddy, as the printed label on the end was saying open pressure of 376 pounds, which confused me for a while until I called up Comp and asked them, he said it was a printing error and the correct number was 336 pounds. (BTW, I bought these around 8 years ago, so I had forgotten all the numbers)

Another reason I don't like CC is because I emailed them twice about the poor test values of the springs and both emails were ignored. I have since read that other people have had poor customer service also.

I am looking at other brands like Isky, Crane, Crowcams, Manley and Lunati and ALL of them are twice or more this price. So I am thinking, how good can these Comp springs be for this price? - look good on paper but in the real world...

So I am wondering if anyone can recommend another spring which will fit Mopar and with similar specs as above? It seems there is not many springs around that will fit. Isky 6005 will fit but they are only 275 pounds and I was wanting well over 300 pounds with this engine and this cam.

Thanks