Don't think I've got a clamp any alternative ways to achieve the same result if you know what I mean or is holding the broken part on and applying pressure for a few minutes till it starts to set sufficient. I've taped things which I'm gluing with masking tap before and I've got plenty of lollysticks which I could stick underneath to support the join while it sets although that would require holding the lollystick or taping it in place while it dries.
DrDalek6,
You can also use elastic bands, holding the parts together and appling slight pressure is great, but remember you will be using a plastic cement which is a solvent and means the plastic item you are fixing is going to melt a bit and as such has a tendency for parts to slide if not held together while the parts set it also takes time for the plastic to reharden after (like 8 hours) and as much as I love holding playmobil close, I rather not do it for 8 hours.
Given your bow spout, how I would approach it is as follows:
Get three elastic bands (2 of such should be 1/2 inch wide (apox 1.2cm) and 2 inches (5.0cm) long like those found on broccoli bunches at the local grocer), the other one just needs to be 1/4 inch wide (0.6cm) and 3 inch long.

You are going to take the longer and narrower elastic band and cut it in half so that you end up with two equal length parts.

You are then going to tie one end of each elastic length to one of the wider elastic bands.

You will then take the elastic band with the two elastic strips affixed to it and pull it open and slide the bigger piece of the plastic bowspot (that is the part not broken off), if it is not snugh twist ( I am going to use this glass bottle as an example
you want the elastic lengths to be at either side
you are then going to take the second wide elastic band and fit it around the piece that is to be reattached. Then slide the elastic lengths under this band and pull the lengths through until a nice consent pressure is applied and the part no longer moves. It does not have to be tight thought. Once you have done this, pull on the broken bit a bit to allow a small gap between the two parts and apply your plastic cement then slowly bring the two pieces back together.
To show you how well this works, I put a full thing of glue inside the jar and affixed the lid upside down so had to use this method to keep the lid closed.


Best part is you can do this for any odd length and it does not leave marks or residue on your toys. If you get a good join you will not even notice it was broken in the first place.
I hope this helps
Cheers,
James