what type of sarung/scabbard fits this keris?

[Gustav]

Green,

I don't know, what do you understand as Lampung style sheath.

There actually are three Lampung sheath forms - one, which is related to Malay Saribulan sheath, the one shown is an old one and is original fit to a conventional size Keris;

a second one, which is very close or even identical with North Coast Java sheaths;

and a third one, which is close or identical to Palembang sheath, with a very typical Selut and hilt style.

Your hilt is a strange one, yet it has the "waist" and waist band, typical for North Coast Java and Lampung. Yet only Lampung hilts (and perhaps some hilts attributed to North Sumatra) show a bigger number of petals arising from the waist band (Sorry Detlef for raiding your pictures). Unusual is the combination with a more or less Java Demam style upper half.

When I wrote "we sometimes see unusual, special blades dressed in oversized Saribulan sheaths in Malay context", it means, that, if such blade would have found its way to Northern Malay Sultanates around 1850 and later, the possibility it would be dressed in an oversized Saribulan is a bigger one.

Please imagine, how an absolutely non-Palembang style hilt with a non-Palembang style Mendak/Selut would look on a Palembang style sheath, which almost always comes together with one or two very distinctive style hilts and Mendak/Selut.