Yes the second one is mine, around 18 cm tall.
I've seen others with the same signature up to about 24 cm tall.
I've some other humppila bits, whci you can see below the main pic - the one on the left is clearly influenced by Nyman (GN 39).
Is yours without the signature unpolished on the base ? (I have another piece similarly unfinished and unsigned).
Twave, where are the bits on designlasi - couldn't find them ?
I'm not aware that Nuujarvi made smaller Serpentini (but am prepared to be proved wrong) - I've seen what I believe to be Nuutajarvi Serpentini in the range 33 - 46 cm.
I've looked in my Humppila book and, whilst it doesn't show this exact piece, there is a similar piece (with three ribbons) 23 cm tall.http://www.suomenlasimuseo.fi/Suomen-Lasimuseo/Ylavalikko/Museomyymala/Tutkimusjulkaisut/Lasitutkimuksia-XIV/
Interestingly this piece is also there. 220516914635 exactly the right height, so it would support the theory that not all were signed.
I would be cautious buying a piece below 33cm for £££ without a suitable provenance.