NO NO NO. Keep your hard earned money.
Deff rollas are easy to make and a great intro to ork scratch building. Magnetize them so you can countinue to change them. I just finished my second and third wagon last night and I am trying to post my scratch built rollas.
1st used a wine bottle cork
2nd used lids of spray on sunscreen
3rd used plasticard.
Oh you could check the gallery for the
WIPs.