I bought the part produced by MEYLE, it got delivered today and I fitted it, shoul'd have taken 1 minute but it took me 10 minutes due to me messing about with the top plastic cover of the strut when that was completely unnecessary as you only need to pry out the bottom retaining clip from the old strut enough for the strut to be pushable out of it's resting position, after which all you have to do is to pull the old strut right away from the top plastic cover and then fit it the new strut.
The part I bought is, 240 910 0002 MEYLE Hood shock fit MERCEDES BM 170 (SLK) (09/96-04/04), made in Germany.
240 910 0002 MEYLE Hood shock fit MERCEDES BM 170 (SLK) (09/96-04/04) | eBay
Do not bother buying the MEYLE brand, it makes a lot more noise than the Stabilus strut and it doesn't pop up fully when you lift the bonnet until you give it a little nudge so it can go all the way up. The MEYLE part doesn't come with the push button either.
I'd stick with Stabilus as it is the original part that was there and we all know it operates perfectly. Next to that I'd only recommend the Febi Bilstein part, there are two that are compatible with the Crossfire, one for about £10, the other for about £37, buy the more expensive part as it has the push button and is guaranteed to be better than the cheaper one. And then I'd also recommend the Lemforder part.