I picked up some painted Perry Cuirassier off of ebay last month.
Although not in bad shape, they were sloppily painted. I chose not to strip them but just tidied up the paint job and gave them a standard.
I opted to give them a Prince Rupert's Lifeguard of Horse standard from Wargames Designs. Was Rupert's lifeguard cuirassier? Probably not, but it gives them some distinction on the games table.
Although there are 8 troopers on 4 bases in Pike And Shotte I would only use 3 bases and they would count as Small.