How much can you actually tailor a raincoat?

[Demodocus]

I've been on the hunt for a raincoat and recently found a classic London Fog mac for a killer price. The only problem is that, while it's marked 38 Short, the model is a 6ft5 tall size L. It appears to be quite snug on him. I'm a size XS to S (168cm/5ft6 and 49kg/108 lbs). I understand 38S corresponds to a size S, but am almost certain it would require some tailoring--36 would be ideal, but difficult to come by. For reference, my wool overcoat is a size 46 (=US36, UK36, S) and comfortably roomy even over a jacket, which is my general preference.

For the price I'm tempted to just go ahead and buy it, but I'd really appreciate some input on how much one can tailor a mac with decent results? Is it a waste of time?

Thanks in advance

 

[maxalex]

This could be expensive and possibly negate your “killer price.” Moreover, ripping out the factory seams might cause leaks although I’m only guessing. I would look for a raincoat in your proper size.