A few years ago, I started to "collect" Yonico bits and bearings. So far, I'm very happy with the brand. You can buy the bearings separately.
Yonico Router Bits
Yonico Router Bit Bearings

 

Plus 1 on the Yonico bits. I have used them in my Bosch router that is attached to my CNC.

 

Infinity has router bit and bearing sets. I have bought and used them. They have both 1/4" and 1/2" diameter bits that come with several bearings of different sizes.

 

I've checked out Infinity bits and found a couple of 1/4" diameter flush trim bits. I've also checked out the bearings, but I'm not sure what the ID is on these bits. I need to make sure the bearings fit on the bit. If I knew the ID I could find bearings to fit.

 

I have been using Yonico bits for about 10 years. Absolutely no problems. I have purchased them directly from Precision Bit’s and from Amazon.

My other go to brand is Whiteside.

 

I checked out Yonico bits and the smallest diameter I can find is 3/8".

 

If you can, please share some photos of your projects. There may be other options available.

 

I would, but I haven't started the project yet. Basically there will be 12 pieces of wood with inner and outer curves that all fit together to form a pinwheel. After the pieces are glued together, the outer part will be cut into a circle. These pieces need to fit perfectly together. The video I've watched shows how to make complementary curves so that fit together with no gaps.

 

I like Yoniko bits as well. I have a whole set for making picture frame profiles. Nicely made.

 

Have you had a look to see if you could use an inlay kit (and template), if both parts are to fit together?

 

No, I haven't checked out inlay kits. Never knew they existed. I'll check them out.

 

I have Amana #47090 1/4" flush trim bit and it worked fine for me for template routing. I don't know if you can get a replacement 3/4" diameter bit. Amana #47189 is 1/4" straight cutter but the guide bearing is 1/2" diameter and not the 3/4" that you want. I have Whiteside BB501 which is a collection of bearing that does have a 3/4" diameter; perhaps Whiteside will have the 1/4" flush trim bit that mates with their bearing set. Good luck. Complementary template routing is fun and can produce some good results.

 

PS: you do not have to buy a inlay kit, as you can use a combination of cutters and GBs that will give you that offset.

For example, The Router Workshop use these sizes for inlays

Internal:

1 ½ “ Guide

¼” cutter

External:

7/16” Guide

¼” cutter