Toilet waste connections

[Rms1]

Hi,
Funny smell from cloakroom toilet waste pipes, so presume a seal had deteriorated. Removed toilets and pipes, which were in 2 parts (see first image) as soil waste is offset from toilet (see third image).
Wanted to replace with a flexi 90 degree pipe, so only 1 connection to soil and 1 to the pan. However, soil waste outlet is 100mm, and can only find 110mm products.
Any ideas as to how to best organise the replacement? Can it only be like the original? (I.e. in 2 parts). Ideally wanted Mcalpine products. Thanks.

 

[Madrab]

That looks like a standard 110mm brown underground soil pipe (OD)? So a 4" finned pan connector should fit without an issue. If it is 31/2" 100mm, then you do get those too but that's usually the Diameter into cast iron and not modern plastic

What does it say on ID rectangle on the black elbow, which I presume was happily connected to the brown soil pipe? Looks like it says 110mm?

 

[Rms1]

Thanks. Yeah it says 110mm on the black elbow. This was connected to the brown soil pipe.
I purchased a mcalister 90 degree flexi pipe as a replacement, but that is a 110mm, not a 100mm, so it’s too small? (See new image).
Thanks again

 

[Rms1]

diameter of soil pipe

 

[Rms1]

Ah it turns out I wasn’t pushing it hard enough! I’ve used fairy liquid as grease, and it’s now fitted perfectly! Thanks for your help.