Found these on line. They are 100 mm dia and the paddle is only 10 mm wide...but I have thought about gluing two together for a wider paddle .

They cost me 70 cents each....probably about 0.45 P. There were also smaller ones being 70mm dia.

Hello Paddlebox Q- these have possibilities for simple models or the basics for conversion. . Where did you source them?. regards, Walter.

Walter,
I was also interested in them and had a search of the internet. I could only manage to find them on AliExpress from a Chinese manufacturer. My thoughts were to use the 7cm ones (with a couple of mm shaved off the diameter), for Vic Smeed's 'Royal Falcon' which is slowly being built. Just not sure about this seller/site and will probably stay with the plan suggested tin-plate ones.

https://www.aliexpress.com/item/1005002766487479.html?spm=a2g0o.productlist.0.0.17647c5bRx8Xgk&algo_pvid=17777f11-7f79-4783-a269-3e3e0dd19425&algo_exp_id=17777f11-7f79-4783-a269-3e3e0dd19425-2&pdp_ext_f=%7B%22sku_id%22%3A%2212000022082921814%22%7D

Tony

Sorry folks too many hobbies....regarding paddle wheels,I found the on Ali express as mentioned by Tony's.