plus I'd have to re-purchase a lot of stock (or hire someone to stick it back
into reels :-) ).
Do you really have so much stuff that's worth salvaging@ - most reeled parts are so cheap that it isn't worth the time reusing.
It is possible to get a useable P&P machine with feeders for under $20k (used) but it is very much down to luck in what you can find used, what condition it's in and whether you have space for something big like an old Mydata TP9.
I'd suggest the best bet is to do some hunting for a subcontractor that suits your quantities and ways of working. Another important aspect, especially when you have a lot of different designs, is to streamline the setup process as much as possble - talk to the assembler about how they like the data, what jellybean parts they normally keep loaded, and minimise numbers of differemt parts (even at the expense of using more parts total).
I currently use a very nice 3D stereo boom video system and full JBC S/Mount stations, but it's becoming too much to do manually.
If you aren't already hand-assembling by stencilling, picking with a foot-operated vacuum pen from laid-out tapes and reflowing, you're doing it wrong and wasting a lot of time - this would save you a ton of time and give more consistent quality.
Even polyester stencils ($10) are perfectly useable for small runs of low to medium density parts, although stainless stencils ($80+) in a decent manual printer ($1-2k) is something worth aiming for as good paste print quality is the biggest factor in final assembled board quality.
As regards reflow oven - a <$100 toaster oven is all you need.
There are a few hints for fast hand SMD assembly in this video I did a while ago: