Miles booster

Hi, only just read about miles booster and I am trying to gain as many miles as I can for trip later in the year(I've never managed enough miles for a reward flight yet) and thought it would be a great excuse for a holiday.I last flew in December to Vegas so does that mean I can ring them up and boost those miles?How many would I get and what sort of money do they charge?
Many Thanks

Miles booster lets you buy either another set of the base miles or double the base miles you have flown. LGW to MCO (return) is, according to Virgin Atlantic, 8672 miles

Miles boosters are always sold at 1p per mile so that means you can buy:

8672 miles for £86.72
or
17344 miles for £172.44

You have up to 6 months after the flight to buy the booster so the Dec flight is still within the time limit. You will need to call Flying Club to buy them though. It's worth bearing in mind that there's sometimes a bonus to the miles booster. The last one was a 20% bonus to the miles from a miles booster in Sep 15.

Buying miles makes sense if you are just short of the amount you need for a redemption. If you need larger amounts it might be worth looking at Raffles' site, http://www.headforpoints.com/ and look at the various methods he covers for earning miles. Common options are Tesco clubcard, credit card signup bonuses, and credit card spend.

Many thanks for your help Stuart ,it has given me something to think about.

It's definitely worth crunching the numbers on the various options to get the flight you want. Is it better to do:

Revenue flights
exEU
pure redemption
M + upgrade
S + upgrade (being generally for companies that will let you book PE as it rarely makes financial sense for those who pay for themselves)

Only once you have worked out all the options can you really be sure you've picked the right one.