0.12c would still be incredibly useful. Proxima Centauri in 35 years? Game changing.
The problem, of course, that with a Bussard ramjet, you won't be able to achieve nearly as much acceleration.
edit: according to https://rechneronline.de/g-acceleration/orbital-speed.php, if I got my numbers right (0.12 x solar mass star, .12c = 36000 km/s), the orbit radius would be 1230 km, so you'd be almost at the core of the star since its radius is ~ 100 000 km.