Jordan for love of god please be carefull it only takes one spec of asbestos and your a dead man ! make sure you wear a mask and if they are breaking up get shot of em !
however you could take some patterns of them if you wish
perhaps share with the community
if i had known you were after turn buckles i could have got some from a local boat chandlry which could no doubt get items such as this.
Cheers
Richard