Yes, and if I recall correctly the price is quite reasonable. Something like 25E if you want just one, but the price drops rapidly to 500E for 5 of them. I suggest you get in touch directly with Raisonance.
In the good US of A , no distributor has that extension card; in fact even the primers2 are hard to get . So you have to learn to do without. and find something locally. so: Before you spend a pile of money and wait for delivery, you better check a local electronics store. 1st you need some connectors Rectangular,Receptacle, Female Socket, 20POS, Pitch 0.100" (2.54mm) ,Row Spacing 0.100" (2.54mm),
Mounting Type: VERTICAL Through Hole, you may want to see what kind of coating you want , like tin for "one off" prototypes or good gold plating (Contact Finish Thickness 30µin (0.76µm)) for long term use
Raisonance is currently producing some extension boards dedicated for the Primer2. They will be available in 3 weeks by now. They will be packaged by 10.