Finding a great pair of vintage slicks is a challenge. Certainly rewarding if you hold out long enough and have success with good rubber. I would encourage you to keep searching and post up what you find. There were plenty of 14" slicks back then too, so if you are flexible on the rim diameter- it will open some options up to you.
M&H also makes a modern made "nostalgic" slick, but I think it might be a bit small for your Chevelle.
https://www.cokertire.com/vintage-drag-slicks.html