Which flash for a SRT?

Hi,

I would like to add some lightning option to my Minolta SRT 303. I am interested in indoor portraits / documentation of my family. Since kids move around and light can be not enough, I would like to have some other options.
I have a couple of Canon Speedlites and a couple of Pocketwizards transmitters/receivers: I assume that those are completely out of question (due to the voltage difference of older cameras). Can you suggest me some way, or even better describe how did you proceed?

Thanks in advance,
Francesco
ps: I am shooting bw film so I am not particularly worried about color balancing.

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The voltage difference would not affect an older camera.
Plug in the sync cord, and get a Graslon Prodigy Flash Diffuser.

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