Unfortunately, the 33669 was the only slanted application intake that was ever made for the HS50 engines. People have used the HS40 slanted intakes (part number 33301) on them but these pictures will show the caveat to doing that
Intake gaskets swapped to show how the ports match up, Left #33669 HS50 intake, right #33301 HS40 intake....
Note the light showing though when an HS40 33301 slanted intake is bolted up to an HS50 block with OEM gaskets.....
Again people have fitted them anyway though, The best ways were to fill in the intake port on the block at the squared off void to get an ever important solid gasket seal as well as being able to match port the flow. I've seen some people twist and tweak till it covers the gaps, tighten it down and call it good though....guess it depends on the builder and how much common sense they have.
Also note that the HS50 intakes (and carburetors) did have a physically larger internal port to go along with the larger port in the block then the HS40 ever did, so you are dropping down a little there as well when doing that.