Wildlife.

Probably been asked before but what is considered a good wildlife lens at a reasonable cost say for the K-3. Would envisage stationery animals or slow moving large birds

The obvious one would be the excellent 55-300mm.

At higher cost, the 150-450mm is splendid.

If I had choice of one lens for wildlife it would be the DA* 300mm F4.
It works well with the 1.4X converter too.
150-450mm is a very nice lens but big and heavy to carry around DA*300mm is smaller and lighter.
A lot of the wildlife photos in my portfolio were taken with the DA*300mm.

I currently use 55 - 300 PLM version which works much better than the old screw drive version which tended to hunt. See my gallery on here for examples including whales and dolphins, birdlife etc Compact and very quick indeed to auto focus.
I've also owned the 300 star F4 which I too loved but found it slower to lock. Never quite convinced of the value of the tele convertor as it meant very shallow hyperfocal range to get all of a creature in sharp focus. With the K3 you can crop heavily anyway. I often crop birds to around 6 megapixels with good results. Not so good in dull flat light when more effort is needed. Learning back button AF has helped a lot.

Depends what you call reasonable ... but in order of cost

Pentax 55-300mm WR
Pentax 55-300mm PLM
Sigma 150-500mm OS HSM (might find one new but otherwise used)
Pentax 300mm f4 (plus 1.4x)
Sigma 100-300mm f4 (plus 1.4x) used and very hard to find
Sigma 50-500mm OS HSM (Same as 150-500mm)
Pentax 150-450mm WR

My favourite is the Sigma 100-300 F4, but I have yet to try the 55-300 PLM on the 2 K-3's at an airshow - and I will be very interested to find out how good it is in the "real world" (from very limited testing, I know it's blindingly fast to focus - but I'm waiting to find out if the tracking is any good - especially on the K-3 II).

OTOH & FWIW, my Sigma 150-500 DG OS HSM will be in the Classified Section within a very few days - partially due to the weight and a bad back and (now) two (!) dodgy knees

My 55 - 300mm is on a K3II for the last year and a K3 for several months before that.Tracking straight at you remains poor. Side to side it's fine. See Buzzard hunting at head of my gallery on here. i've used this lens back to my whale and dolphin pics in the Caribbean in same gallery. It was foreign travel that got me away from bulky star prime. Apart from wishing I had a F2.8 for the light I'm happy with my results.