Commercial available discrete OP-AMPs - Overview wanted

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... discrete OP amp project, which use the internal topology from Burr Brown's OPA161 ...

I think that might include a typing error. There exists no IC called OPA161 , perhaps you meant OPA1611 (seven characters not six). And I myself haven't seen a full schematic of the OPA1611 internals which shows every single transistor and every single capacitor and every single resistor. Perhaps one exists, but I haven't stumbled across any.

edit- the original paper by Dennis Monticelli can be found (here) .
 
Manufacturers don't broadcast their intellectual property like this, you're unlikely to see anything like a full schematic for a modern chip without signing an NDA. Its all simplified equivalent circuits if you see anything, or perhaps just the pin ESD protection - topology you may be able to infer, but not details.

Anyway even if they did there's no way to build an inter-digitated matched input pair with laser-trimming in discrete components, so there's no way to get input pair performance to match most precision opamps. And the multiple-emitter transistors used in ICs are also a problem!