Sequences on Export - is it possible to do this?

I have a number of images that I want to export into the same location, using a specific numbering sequence:

{Job Identifier}_{sequence}

*but* .. I want the sequence to reset at 1 for each Job.

So if I have job_a with 4 images, job_b with 2 images and job_c with 3 images, I want to see:

job_a_01.jpg

job_a_02.jpg

job_a_03.jpg

job_a_04.jpg

job_b_01.jpg

job_b_02.jpg

job_c_01.jpg

job_c_02.jpg

job_c_03.jpg

So essentially, I'd like the sequence to increment so long as the filename continues to be non-unique, and reset to the start when an otherwise new filename is generated.

LR sort of does this if I just specify {Job Identifier} for file renaming, but the output is:

job_a.jpg

job_a-2.jpg

job_a-3.jpg

job_b.jpg

job_b-2.jpg

..etc

This doesn't quite have the desired effect because the names are consistent, and nor can I specify a padded numbering format (eg, job_a-001.jpg)

LR does not appear to be able to do this natively, and I haven't found a plugin that could help me either.

The alternative that I'm currently using is {job Identifier}_{<timestamp>} but using clean sequential numbering would be preferable.

Is there a way?