That's not a good idea!
The questions are no longer based on it. If you want a slide computer and want to pay £70, the AFE ARC 2 is of much better construction, as is the Transair effort. Back in the day, the CAA used to keep 3 CRP-5s in their office to take an average, as it was so badly made, aside from inheriting some inaccuracies from the RAF one on which it was based that we had to use (with arrows all over it - you felt like a prisoner!) I don't think the situation is much different today.
The sine based machines like the CR-3 are much easier to use.
G