Spark plugs for R1150 engine

I need to service my bike and is looking for spark plugs. The manual specification list NGK BKR 7 EKC & NGK DCPR 8 EKC as standard for this bike. The agents quote R175 per plug (iech!) and Midas only R64 and R43, but they do not have stock of the NGK BKR 7 EKC only NGK BKR 7 EKU. What is the difference between the C and the U at the end of the number. Will this be harmful to the engine?

Midas only stock NGK DCPR 8 E (one electrode) in stead of NGK DCPR 8 EKC with e electrodes. Can I go for this?

Any other shops I can try?

When did you buy the bike - is the gaurantee still valid - 24 months for new bikes. Read the other posting started by Sias in this regard.

No, not new - 2003 model. I used to do all servicing myself and know how to change spark plugs.

I managed to locate NGK BKR7EKU spark plugs from MIDAS. According to the salesman they are similar to the NGK BKR7EKC that is the standard plug, but the gap on it is 1.5mm out of the box an the standard on is .8mm. Midas suggested that I can make the gap smaller to the BMW spec, but should I buy it and do it?

Any feedback if it will work, please.