I purchased a teak garden table and chairs a while back. Unfortunately a number of the bolts that connect the chairs, and act as pivots when the chairs are folded, have broken and need replacing. The original company seems to have gone out of business. I can best describe these bolts as brass sleeved bolts – both ends have a carriage bolt slotted type head (without the normal protrusion under the head itself) and one part has a threaded sleeve (female) and the other part has threaded shaft off the head (male). I’ve tried hardware shops and the Internet but cannot locate a source for replacements. Really grateful for any pointers