If you don't mind going the used/refurbished route, an I3/4gb/500GB Dell or Lenovo desktop (I'm not a fan of HP) with a valid win8/10 license can be had for under 10k from many reprocessors. A basic 19-21" monitor (Zebronics/LG/Samsung) can be had new for 5k. This puts you just at or slightly over your budget, when you include the printer linked above.
Slightly harder to find, but a pentium dual core version of the same desktops can be had for under 7k. A core2duo desktop will be even cheaper.
Depending on where you live, you might even be able to snag a used I3 Lenovo ideacentre All in One for 10-12k. A used Dell or Thinkpad laptop with an I3/4GB/500GB configuration can also be had in the 12k range.
Unless the software you want to run is very lightweight and can run on a celeron class processor, I don't think a new desktop+monitor can be had for less than 15k.