Rosemont Stud's Anthony Mithen has added to his Tavistock collection, buying a half-sister to multiple Group One winner Volkstok'n'barrell in New Zealand.

Mithen is a part-owner of Volkstok'n'barrell and Victoria Derby winner Tarzino, also by Tavistock.

He went to $405,000 to buy Galaktika at the broodmare, weanling and mixed sale at Karaka on Wednesday.

"I think she made every penny of her worth and she is obviously a sentimental buy as well," Mithen said.

The mare will eventually make her way to Rosemont in Victoria but for now will stay in New Zealand and return to Tavistock after she has foaled.

"We have a couple of nominations locked away to Tavistock and probably that is the obvious mating this year," Mithen said.

"But in time she has been bought to go to Tarzino, who races in our colours and will retire to stud somewhere in the future."

Mithen also paid $100,000 for Volksbelle, a three-quarter sister to the dam of Volkstok'n'barrell, also in foal to Tavistock.

The Donna Logan and Chris Gibbs-trained Volkstok'n'barrell, third in the Hollindale Stakes at his most recent start, will attempt to add another Group One win to his record in Saturday week's Doomben Cup.

"His run was excellent given he was probably not fully wound up," Mithen said.

"He missed a gallop during the week, just through circumstances and not being able to get on to the track.

"To come home on that track from last was very encouraging going to the Doomben Cup. I think he is back in a big way so it is really exciting."