A few weeks ago, a cosplay maker group called 1/3 Delusion launched a trailer featuring their latest cosplay outfit for Doctor. They are selling the Doctor outfits for ¥477 (RMB) which is $70 (USD) or ¥7635 (JPY) on the Taobao store. Here's the showcase video.
Also, the group has previously produced other Arknights cosplay outfits with showcase trailers.
For more details, feel free to visit their Doctor outfit store page and YouTube channel.
Taobao (CN): https://item.taobao.com/item.htm?spm=a1z10.5-c-s.w4002-21271248398.82.70ec731atKhe4B&id=598464474186
YouTube Channel: https://www.youtube.com/channel/UCLeTOMKZQB7TFjHIJiZybPQ/