Power steering in a slant 6 to 318 swap

Your existing PS pump should work just fine. You will need to find brackets to mount it to the V8. Hoses might be a toss up though. The return hose will be easy, but you may have to get the pressure one made if you can't find an off the shelf hose. Most NAPA stores make hydraulic hoses nowadays. You will need an Early A body drivers side exhaust manifold to clear the PS box in your car if you aren't planning on headers.