If they are just straight pins you could just use a suitable size of drill bit, I've done that before.

I've no idea of the sizes for your engine but, the last Renault timing belt I did I used an 8mm drill to hold the flywheel in position.

£20 for the correct timing tools sounds like an absolute bargain to me .

Compared to possible alternatives, yes indeed.

Try your local dealer-one of our locals (not Nissan) used to loan tools against a deposit.