1969 Z28 heater core-best quality replacement?

[JST69Z28]

I am replacing the seals in my heater box and also want to replace the heater core.  I replaced it 42 years ago (it was leaking inside the car) when I got the car.  The existing core still looks good, but I didn't want to risk reusing the old one so ordered one from HBC.   I just got it, and it is much lighter in weight then the old one, plus the hose tube solder joints don't look that strong.  The 5/8 tube is bent at a different angle than the one I took out, so doesn't fit even with making the firewall hole a little larger.  My only option is to bend it and possibly to get a local radiator shop to strengthen the solder joints or return it and find a better fitting and higher quality unit.  I read 2 posts on another Camaro forum where the members had problems with the TSM branded core leaking, and that is what I got from HBC.  I have reviewed previous CRG posts, most are 5+ years old, and was hoping there may be new information available. I'm not impressed with the quality of this new core and am looking for recommendations from members where to find the best quality.   

[169INDY]

Hum.

I chose this route:

Sent my Factory Harrison core to Glen-Ray radiators for rebuilding.

www.restorationradiators.com
Glen-Ray Radiators Inc

In Fact I scan local swap meets for SBC-BBC used Harrison cores Cheap for rebuilding stock as insurance for the vehicles I have, so that is also an option. A Prior owner ordered a weird ALUM core that has fitment & outlet-Inlet issues i was unwilling to accept.

FWIW

[Dave69x33]

I agree with 169INDY, I would first have a radiator shop leak test your original heater core and solder repair it if needed. I did this with my radiator and it has worked well since...which has been over 6 - 8 years ago.

[JST69Z28]

The current heater core isn't original.  I wish it was, but in 1982 when I replaced it, I likely threw away the original Harrison core.   Back then, I had no idea about preserving original parts.  There is no brand marking on my old one.  Still open to feedback on any higher quality replacements that are available today. 

[Sauron327]

I've had original heater cores and radiators done by Glen-Ray. If you go aftermarket, at the very least have the necks resoldered. Many times they leak or are not positioned corrrectly. A good local radiator shop can recore a Harrison. I found one in my area. You could ask at Team Camaro what repro one is decent. Some had good luck with Rock Auto. I might have a couple Harrison cores left in stock I don't need. That's why I saved them from parted out cars. Glen Ray may even have some.