About 15 years ago, give or take, I ran across 3 factory rimfire conversion kits for a FAL.  I bought them, sold them back off because at the time I only had a FAL with DSA's 11" barrel and the kit used barrel liners for full length FAL's.  I was such an idiot not realizing how rare these kits were.  They were very nice with barrel inserts and weighted magazines.  I have never seen a kit for sale before or after.  Has anyone?  I would sure love to get one of those kits again.

I’ve only seen one or two for sale Over the years… I think they were originally made for the German army and sold in a wood case if I’m not mistaken

HK made a bunch for the G1.

Yes, they came in very nice fitted wood cases, top quality. I think 2 magazines and they were weighted to feel like they are loaded with 7.62.  Full length barrel insert.  The company I recently bought a select fire FAL from mentioned having them, but they didn't really have any.  I really can't believe I actually once bought three kits at the same time, thought nothing of them, and just got rid of them.  Definitely one of my greatest mistakes in the firearms world.  Another was choosing to buy a dealer sample select fire FAL when it was only $200 cheaper than the other three transferables being offered back in 2000.  The transferable today is worth 10 times what I paid back then for the dealer sample.  Sigh...

A guy made some about 10 years ago on FALfiles.

kurbelgehause is his user name.

https://www.falfiles.com/threads/new-production-22-fal-conversion-kit-project.304586/page-7#post-3126344

Just FYI.

He upgraded one of my kits to run full auto.

I had no money when he did his run.  He keeps saying he's planning on making more, but I'm still waiting.  I really want one of his kits.

Over the past year a few have shown up on GB......
(I usually found them on a "Erma conversion" search.)  
Erma was one of the companies that made them, along with HK.  
Though, supposedly, the HK ones work much better.  

I have 2...... a metric and inch pattern.....  

It's just the magazines have the respective lug on them..........  
Shoot well...............  

I pieced the inch one together....... I found a barrel, then BCG and finally the mags.  
Had a local woodsmith copy the box..........done and done.

Yep, and his kit runs great. I'm sure if he made more they'd sell out. I still need to make a storage case for mine, come to think of it.