6.8 ohm 10W resistor:
Xicon 5% Cement Power resistor, axial leads.
Mouser part num: 280-CR10-6.8
Price each: $0.55
24 uf 250V capacitor:
Closest I could find (I didn't search all of the catalog) is a 22uf 250V in several styles. It would probably work fine - large value electrolytics have a very wide tolerance range. However, you could add a 2.2uf in parallel with the 22uf to get an equivalent 24.2uf cap.
Nichicon Aluminum electrolytic capacitor, UVR 85C General Purpose Series (lead free):
22uf 250V
Mouser part num: 647-UVR2E220MHD
Price each: $0.61
2.2uF 250V
Mouser part num: 647-UVR2E2R2MED
Price each: $0.31
(These are radial lead, polarized electrolytics. If you need NPO, or want axial lead or other styles check Mouser's catalog.)
I copied these from Mouser's Nov - Jan 2005 printed catalog. Please check
www.mouser.com online for correctness and ordering info.
Good luck!