Correct Direction

Most any good 360 block you find will be fine for a street cruiser/weekend bruiser. But, since you asked for recommendations, here's what I would look for:
1.) '88-ish through'92 360 roller block. Already has roller lifters, comes with windage tray and attaching hardware from the factory, and being TBI motors they're usually in pretty good shape as far as cylinder wear goes. They come with 308 heads, which if they're in good shape, are a good head and you can resell to offset other costs.
2.) '93-'94 and maybe '95 5.9L (Magnum) 360. Again, usually really good on the cylinder wear. You want the early Magnum blocks because they're still drilled for oiling through the deck/heads, and are compatible with your Speedmaster heads.
Try to keep the SCR around 9.5:1 or a touch higher for a street octane-friendly setup. For a cam, try something along the lines of the Lunati 20200715. Not over the top, but a torquey, fun cam with good street manners.
Your issue will be with the clutch. Early A V8s had a wimpy 9 1/2 (?) inch clutch. Brewer's sells a scalloped 10" disc that fits, but you'll be better off upgrading to the later 10 1/2" components. Brewers can set you up with anything you can't source locally.