Radiology is less competative than Ortho, but more competative than Gen Surg.
So, if you want to try the Vasc Surgery route, you would need to get a Gen Surg residency and apply for a Vascular fellowship. I don't know how competative those fellowships are, but my guess is that it's not too bad.
If you want to do IR, you need to match into Radiology, and get an Interventional fellowship, those are easy to get (like most rads fellowships).