I have built custom packs in the past and will do it under special circumstances but the usual answer is no as I am at like 110% workload at the moment.
Packs take a long time to build properly and I have a strict policy of delivering stuff when I say I will for Street Wing, so i would rather turn down a sale than keep someone waiting and annoying them.
yeah I do, but I paused it. For UNiK, I ask a supplier made in France to build them. I would recommend any of the names you mentioned. They are all dope and reliable builders.
I also bought from @hyperIon1 & @hyperIon2, they have great customer service and my battery is still serving me well after 130+ miles! Just email or PM them