I restored an Optimus 8R last year : r/CampingGear
Vintage Optimus Radius No.5 Camping Stove Swedish & Twigg Clone British + Bonus | eBay
Optimus 8r Stove - Etsy UK
Antique Oil Stove, Russian Stove, Soviet Russian Red Army Portable Gasoline Stove Primus Optimus 8R Clone. on a White Background Stock Image - Image of accessory, design: 229242283