Mk2 FL Rear Wiper arm Estate vs Hatch

Long story short  - I am trying to avoid buying a genuine new estate wiper arm £43!

I can't find any listings for the mk2 Estate wiper arm from any of the quality after market manufactures, even though the original says it is made by valeo.

One motor factor on ebay said they wouldn't supply the hatch vaico v1-0-9625 replacement, as it is not on the compatability list. But it looks very similar. I think the only difference maybe 310mm length for estate, 330mm for hatch, in which case I think it will work with a slightly larger arc.

Anyone know for sure?