The pressure they are sold as is the max pressure. So if anything you’d get less.
You’d want Atleast 70psi in my opinion for window cleaning.
^^^ That's why Shurflo upped the pressure to 100psi from 65psi for window cleaning G&M. 65psi was sufficient for short lengths of 1/2" hose. Using 100m of minibore and microbore needs higher pressure to give a reasonable flow.
Shurflo make lots of pumps for many different applications and materials. If they could get away with making fewer, trust me, they would.
Also be careful when buying Shurflo pumps. A couple of years ago one of the suppliers was warning us about Chinese copy Shurflo pumps in the UK market place. Amazon and Ebay are ideal platforms to offload this type of product. Saying that we haven't heard anything about this recently.