A Proficiency Check is much less onerous than a Skill Test:
Usually Steep Turns left and right, 2 x Stall Recovery, a PFL and 3 circuits and shouldn't take more than one hour.
Navigation is not a Mandatory Item for an SEP Revalidation and is at the discretion of the Examiner. Most would just ask for a short leg (maybe even just a diversion).
As your SEP has not expired, this is a Revalidation so, no need to approach any Instructors, if you think you are capable just book an Examiner.
This, in my opinion, is a much better approach than trying desperately to get the required hours in for Revalidation by Experience. Which, if you are not successful your Rating will expire. This, then becoming a Renewal where, although the Proficiency Check is exactly the same, you now need to be 'Recommended for Test' by a Flying School.