1. nice car
2. I'd stick with OEM skirting from Porsche, unless you are buying directly from Tech Art. I'd avoid buying fiberglass from not very well known aftermarket sellers.
My MK2 skirting is from one of these shops that hand make the skirting and the fit is not perfect but not bad enough to send back for a refund.
The OEM stuff is a perfect fit 100% of the time because it's lazer cut and comes from one mould. The fiberglass stuff is hit or miss. And being in Australia I'm not sure I would take the risk with a small company.
If I were you I'd get the GT3 front bumper and add OEM side skirts. Or talk to Tech Art or one of their local authorized reps.