Hi - are you still needing a response on this?
Although they call what you are wanting to change the 'lower' arms' there are no front upper ones. Rear has upper and lower arms.
From your description I would suggest you are referring to the front 'wishbone' as the control arm (interchangeable terms). This is all a slippery slope - you can either change what it necessary OR do a complete refresh.
From experience once you start replacing one worn part with a new fresh firmer item it shows up all the rest of the old failing bits and likely speed up the ware on those old bits.
I have recently done a full suspension overhaul on a 2010 Tiguan 4motion. Literally everything, all arms, anything rubber, springs, shocks, arb's, subframe collars, ... you are in for quite a lot of money but it will be really really good and you can get bits on from other VAG models too to improve things. Depends on what you want to achieve. I've gone for preventative maintenance along with making it less of a truck as we are keeping it at least another 5 years so will get the benfit from all the new goodies.
I decided to do it all together as once you get close to lowering the front subframe there are several parts you can change OR will have to drop the subframe again for in maybe 6-24 months again with the associated labour costs and (ideally) another set of new subframe bolts if you adhere to the VW 'use once' philosophy of their bolts.
Personally, I would get the alloy Passat wishbones and a Meyle HD rear console bush. The HD console bush doesnt have the large holes that rip - less ware and lasts longer. Alternatively there is, I believe the genuine S3 rear console bush which is also either solid or has less voids.
For the wishbones, as the alloy ones are essentially fine buying used, get a used pair off of ebay and just get the front small bush replaced. I have done this before by drilling out the old bush and inserting a poly item from Problem Solving Bushings. That bush will never need replacing again.
If you have an auto/dsg then the (UK) passenger side will be a problem and likely the subframe will need to be dropped a bit.
I found once you start on the front chassis parts, if you really look in to it, its a very slippery slope ... because if you are dropping the subframe do you then replace the front ARB rubbers (integral to the ARB unfortunately and requires subframe removal ...)
Also, ECS subframe collars will put your front subframe in correct alignment permanently, while your subframe is being lowered...
Happy to detail more in a more detailed response below if needed ...