What is Reddit's opinion of The Army Painter Miniature and Model Files - 3-Piece Diamond File Set of Round File, Flat File and Triangular Metal File - Needle File Set for Metal, Resin, and Plastic Miniatures.?

From 3.5 billion Reddit comments

I ordered a set of these just for the occasion. https://www.amazon.ca/gp/product/B001AE7RRO/ref=as_li_qf_asin_il_tl?ie=UTF8&tag=3dprintedtabl-20&creative=9325&linkCode=as2&creativeASIN=B001AE7RRO&linkId=0818deea100a21fd61e9bc084bf72017

As to the files, I found some on Amazon for $6.90, though they're actually files specifically for miniatures as opposed to jeweler's files.

This is what I used for files:

https://www.amazon.com/Miniature-and-Model-Files-Set/dp/B001AE7RRO/ref=sr_1_2?ie=UTF8&qid=1498081654&sr=8-2

Not sure the grit, but they work great!

As for bits... What are you using to pin with? I started with Privateer Press models so I just got their pinning set. Comes with a bunch of metal to pin with and then 2 or 3 bits. Work great for me! It was one of these three, I forget the exact size I bought:

https://www.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Daps&field-keywords=P3+Pinning+Expansion

As for getting more bits: I would just search Amazon for pin vice bit set or just pin vice set. That will be what you're looking for. I don't know of any place that would sell individual sets of small bits except for a specialty hardware store or a hobby store(Michaels, ACMoore, etc)