You are right, cam cleats would normally be spring loaded, these sound like they are past their prime.
Do yourself a favor and replace any hardware that looks "iffy" in any way. This goes for any of the lines as well. The thing is, once you are out on the water, and something breaks, you can't just pull over to the side to fix it. Especially if you are a newbie, you are relying on the hardware to work, because you don't have the skills (yet) to improvise around a broken piece of equipment. I had one of the original jib tracks break off during the maiden voyage. Luckily, I had an experienced sailor with me, and he managed the jib, and we got back fine, even though our return was upwind against a building wind. Once back in town, I tossed out the old tracks and replaced them with whatever modern equipment I could find that was of the right size. It's functional, looks good even though it's not original, and, most importantly is considerably stronger and more reliable than the original fittings ever were. I've never looked back.
Like you, I have a '63 DS 1, and some parts have been replaced twice (were already replaced once by the previous owner and then again by me). These things do have a service life that's less than that of the hull... However, some parts are clearly in good working order, and I've seen no reason to replace them. The original main sheet swivel block with cleat is still going strong, after all the other blocks, sheaves and cleats have given up and have been replaced. One block on the boom I replaced not because of service life issues, but because I wanted to replace it by a
ratchet block, which makes holding the mainsheet much easier and is an upgrade I wouldn't hesitate to recommend to anyone, whether new to sailing or not.
Here is a link to some cam cleats that would make suitable
replacement cleats for the jib sheets (line size up to 3/8"). Or
these.
Are you ready?
If you pick a day with moderate winds (not more than 6-8kts) then I think you'll be able to work out by yourself how to translate the theory from reading into some practice. Bring a trusted pal as crew or someone with more experience than you.