Hi - DO NOT PLAY is my advice.
No matter how much strengthening you do to your knee, it will not support you when you need it to. There are a lot of different reasons for this...what you need to know is that you shouldn't do it!
Lots of people get away with not having surgery but they usually don't play rugby.
And to be honest, unless you will be paid LOTS and LOTS of money to play, is have premature arthritis and pain during winter and not being bale to climb stairs or slopes later in life worth playing right now??
Good luck. I know what i would be doing...can you pay to have the operation?