Pretty sure you'd need three front rowers regardless of one covering hooker, so he could have three props, one of them also covering hooker, but I think that aspect of it is more thinking out loud/thinking about squad number limitations (drop your third hooker for an extra backrower, have one of your props as emergency cover if required)2 props (1 covering hooker?)
I could definitely see them going for a 7:1, especially if they can get Quirke on form as he's played some wing before 0 - maybe they'll get Marcus some runs at 9