Question:
Hi.
Any information Please. The Backstamp is a black H. Inscribed on the base is 158 AUSTRIA. The model looks to be 1960s in style semi-matt finish. Made from red clay.
Answer:
Hi Colin,
Welcome to here and the to Pottery Forum.

I have looked in a few of my books and there are several "H" marks, so I will need an image to be able to go any further.
Answer:
Hi Elizabeth.
Thank you for your time, how do I put an image on this board??
Regards Colin
Answer:
Hi Elizabeth.
Thank you for your time, how do I put an image on this board??
Sorry I think I have found out lets give it a try.
Regards Colin
Answer:
Hi again Colin,
Thanks for the image, unfortunately I have looked in the following books and your "H" mark was not in them.

Marks on German, Bohemian & Austrian Porcelain: 1710 to the Present by Rontgen,

Miller's Pottery & Porcelain Marks by Lang,

New Dictionary of Marks: Pottery & Porcelain: 1850 to the Present by the Kovels, and

Dictionary of Marks: Pottery & Porcelain: 1650 to 1850 by the Kovels.

Hopefully someone will come along and help you identify this piece.
Answer:
I checked my Concise Marks & Monograms on Pottery & Porcelain by William Chaffers and I couldn't find anything either. Sorry!
Answer:
Hi Both.
Thank you for trying I have drawn a blank on all my checks also.
Regards To you all
Colin