Waste connections to cast iron saddle

[dilalio]

Morning all.

Have an existing internal cast soil stack servicing a bathroom.
Connections to bath and basin are made via plastic flexis connected through round saddle doors in the stack.
Want to replace with rigid pipe and am looking for a fitting that will do this. Don't know if the existing has been bodged or an actual fitting exists to go through the saddle door.
Can anyone shed any light on such a fitting?
Cheers.

Existing looks like this...

 

[dilalio]

Edit above...

Existing door is much smaller say 1.5" into the 4" stack.

 

[Madrab]

Do you mean removing the inspection/rodding cover and then getting a saddle that fits onto the flange and uses the bolt holes? Can't say I've ever seen one exactly like that.

Not an option to use a normal 4" cast saddle clamp that will fit onto the plain cast pipe once a hole's been cored?

 

[JimCrow]

Thats "Timesaver" you have there, they do a strap boss,

 

[Hugh Jaleak]

Think we need a picture of whats there currently, so to determine what type of fitting and/or seal is present, This would help advise your best course of action, whether the fitting needs total replacement or the existing connection can be reused.

 

[dilalio]

Had another look today chaps, it's a bit hectic as I'm also trying to sort out re piping the dwelling and it's on a council block with a private leaseholder who is spending a fortune to make it his own.
It has district heating and hot water primaries on a 3 pipe system, which will be changed to 2 pipe in the next 3 years.
I'm trying to install it so the client can use the supplied services with a UV cylinder and UFH system now and have it ready for the changeover, when it happens, with no internal disruption of decor and fabric... Its a bloody nightmare.
I'll get some photos but it looks like wastes have been fashioned into existing saddle plates on bosses... No strap on's or such like. There is no room for these to be added to the stack. It's a case of re-use the existing connection points.
Cheers for the assistance.
I'll get pics when next on site.