door knob for UPVC front door – any specialists??

this chap (too smart for his own good) has learnt to silently open the front door and make good his escape.

we’ve been locking the door when we are in now but he seems to know when you’ve forgotten and does it again, also, its pretty inconvenient locking the door all the time.
i’ve found (on ebay) a replacement euro cylinder with a thumb turn on the inside to make it a bit less hassle – is there any good reason why this £8 one will be less good than a £22 yale one??
What i really want is to replace the handle on the inside with a knob. i’m then safe till the fleabag evolves thumbs
current handle looks like this
and if my measurements are correct, its a 92PZ. i cant find any replacement knobs, just handles, or some that have a wee stubby handle but on the outside. any ideas??

Try screwfix

There is a chunky square shaped knob available, in the push down mode, will look for details asap.

Depending on the handle you have at present you may be able to rotate the inner handle to the vertical/up position then see if Rover can work out that conundrum. Afaik there isn’t any knobs to replace the levers, not from my suppliers anyway.
With regards to the Euro cylinder, as long as the 60/40 split is the same size as the existing cylinder it’ll be fine to swap like for like.

Tried changing the handle to vertical but it fouls the wall when I shoot the deadlocks.

Please excuse a bump for the Saturday evening crew….

There is a pad type handle it still pushes down or just replace the cyclinder with a thumb turn, problem is if the thieves get in they only have to turn the thumb turn to escape.